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All my EFI partitions have the same uid!!!

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I've just had the idea to check the uid of the EFI partition of 3 drives and (see title)...
Now I understand why Clover Configurator can't open 2 of them at the same time, it's as it was the same drive for him.
So, is this normal? Should I do something about it?
I suppose there's a Terminal command to change that?

EDIT: well, I've been a bit fast on this one... After googling that uid, it seems like every (or many?) EFI partition in the world has 0E239BC6-F960-3107-89CF-1C97F78BB46B as their uid...
So should we do something about it? Can we? Is it safe?
 
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UtterDisbelief

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Interesting! I just checked my two OS X drives and indeed that is the case. Same number. The Win10 has a different number.

Yes, same here.

I'm guessing it is safe because the EFI partition is emulating the hardware of a real Mac, not actually a drive that is used. It is, after all, formatted as MS-DOS so not something OS X / macOS would be looking for.

Having said that, I'm no expert! :rolleyes:
 
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0E239BC6-F960-3107-89CF-1C97F78BB46B

Same number.

Yes, same here.
The EFI partition type is not really an MS-DOS partition...

13.3 File System Format

The file system supported by the Extensible Firmware Interface is based on the FAT file system. EFI defines a specific version of FAT that is explicitly documented and testable. Conformance to the EFI specification and its associate reference documents is the only definition of FAT that needs to be implemented to support EFI. To differentiate the EFI file system from pure FAT, a new partition file system type has been defined.

EFI encompasses the use of FAT32 for a system partition, and FAT12 or FAT16 for removable media. The FAT32 system partition is identified by an OSType value other than that used to identify previous versions of FAT. This unique partition type distinguishes an EFI defined file system from a normal FAT file system. The file system supported by EFI includes support for long file names.

The definition of the EFI file system will be maintained by specification and will not evolve over time to deal with errata or variant interpretations in OS file system drivers or file system utilities. Future enhancements and compatibility enhancements to FAT will not be automatically included in EFI file systems. The EFI file system is a target that is fixed by the EFI specification, and other specifications explicitly referenced by the EFI specification.

So when initializing a system partition, Apple may use an image of a conformant partition rather than using FAT file system tools (newfs_msdos) that might change or evolve over time, whereas the partition type specified by the EFI specification type will not.
 
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It's a bit boring when you have to open 2 EFIs to compare 2 config.plist, for example... I've managed duplicating Clover Configurator and have each one open a file. ;)
(or temporarily copying one on the desktop, when using BBEdit to find the differences)
 
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I'm currently trying Mojave and I've noticed that the confusion doesn't occur there!
At least, Clover Configurator (same version I use in 10.11) opens config.plist on different EFIs, even by drag and drop with no issue.
Looks like the OS is reporting a different UUID to apps, or something similar. ;)
 

UtterDisbelief

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I'm currently trying Mojave and I've noticed that the confusion doesn't occur there!
At least, Clover Configurator (same version I use in 10.11) opens config.plist on different EFIs, even by drag and drop with no issue.
Looks like the OS is reporting a different UUID to apps, or something similar. ;)


Hi there. Long time, no speak :)

I wonder if you can manually change UUIDs. Terminal will generate one for you if you need it, though how that would be of any use in a part of the system macOS never sees, I'm not sure...
 
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